Reinforcing structure for direct flow steam dome for condensers



y 14, 1968 R. J. STOKER ETAL 3,382,918

REINFORCING STRUCTURE FOR DIRECT FLOW STEAM DOME FOR CONDENSERS I5Sheets-Sheet l Filed Aug.

INVENTORS ROBERT J. STOKE BURTON PAUL ALAN SOLER y 1968 R. J. STOKERETAL 3,382,918

REINFORCING STRUCTURE FOR DIRECT FLOW STEAM DOME FOR CONDENSERS FiledAug. 1, 1966 5 Sheets-Sheet 2 INVENTORS ROBERT J. STOKE/i BURTON PAULALA/V SOLE/i May 14, 1968 R. J- STOKER ETAL REINFORCING STRUCTURE FORDIRECT FLOW STEAM DOME FOR CONDENSERS Filed Aug. 1, 1966 Q \F I 6 001:

\\ FIG. 7 [I [I l] [I I] i 42 3 2 l I 4| I05 FIG. 6

INVENTORS ALA/V SOLER 3 Sheets-Sheet 5 United States Patent 3,382,918REINFURCING STRUCTURE FOR DIRECT FLOW STEAM DOME FOR CONDENSERS RobertJ. Stoker, Phillipsburg, Burton Paul, Princeton,

and Alan I. Soler, Cherry Hill, Ni, assignors to IngersolI-Rand Company,New York, N.Y., a corporation of New Jersey Filed Aug. 1, 1966, Ser. No.569,439 11 Claims. (Cl. 165-67) ABSTRACT OF THE DISCLOSURE Thisinvention relates to a steam dome for use in combination with a surfacecondenser of generally standard configuration.

It is generally recognized that as the steam flows from the turbinethrough the steam dome and into the condenser, and as the steam reducesin volume as it condenses into its liquid form, a vacuum is created inthe dome. This vacuum causes a great deal of pressure to be applied tothe steam dome and without some means of support, the dome willcollapse. Prior methods of supporting the steam dome generally comprisedinternal structural bracing in the form of heavy pipe generally addedwherever it was felt necessary, and wherever there was room and mostoften in a lattice configuration spaced at various levels of the steamdome. These methods of bracing the steam dome provide a structurallysound configuration but steam flow is so adversely affected thatcondenser performance is reduced.

Therefore, it is the principal object of this invention to provide adome for use in combination with a condenser which provides good supportfor the dome but does not interfere with flow of fluid to be condensed.

It is a further object of this invention to provide a steam dome whichwill increase the efiiciency of a condenser.

In general these objects are carried out by providing a shell having aninlet for receiving fluid to be condensed and an outlet for dischargingthe fluid into the condenser. First structural means in the form of aclosed ring such as a hollow beam is provided at the top of the domeadjacent to and around the inlet to prevent the dome from collapsingaround the inlet, and second structural means is provided at the bottomof the dome adjacent the outlet to prevent the dome from collapsingaround the outlet. Brace means such as ribs are mounted internally ofthe shell between the first and second struc tural means and locatedalong the surface of the shell for transferring the load due to thevacuum on the shell from the shell to the top and bottom structuralmeans. These ribs are mounted so that their longitudinal axes extendsalong the shell in a generally vertical direction and are of such a sizethat the inside of the dome remains substantially unobstructed therebypermitting free flow of the fluid from the inlet to the outlet. The ribsalso direct the flow of steam from the inlet to the outlet and may beplaced so that the steam will flow in greater proportion towards thecold end of the condenser.

These and other objects will become apparent from the followingdescription and drawings in which:

3,382,918 Patented May 14, 1968 FIG. 1 is an elevation of the steam domeof this invention connected to a condenser with parts being broken away;

FIG. 2 is a fragmentary detail showing that portion of the steam domeoutlined by the circle 2- -2 of FIG. 1;

FIG. 3 is a fragmentary detail of the steam dome outlined by the circle33 of FIG. 1;

FIG. 4 is a section taken on line 44 of FIG. 1 in the direction of thearrows;

FIG. 5 is a fragmentary detail of a portion of the steam dome outlinedby circle 5-5 of FIG. 4;

FIG. 6 is a cross-sectional elevation of a modification of thisinvention;

FIG. 7 is a top plane view of the steam dome of FIG. 6; and

FIG. 8 is a view similar to FIG. 2 showing another embodiment of thisinvention.

Referring to the drawings, the steam dome of this invention generallyindicated at 1 is shown as trapezoid in configuration but may be of anydesired shape. It is open at the top to provide an inlet 2 and open atthe bottom to provide an outlet 3. The outlet is connected to a surfacecondenser generally indicated at 4. The condenser includes a pluralityof tube bundles such as 5 having an inlet 6 and an outlet 7 for coolingwater. In some applications the steam dome may be an integral part ofthe condenser.

As is conventional with steam domes, there may be a heater pipe 11 withextraction piping (not shown) for removing some of the heat from thesteam and preheating feed water for the turbine or for use in otherplaces. Fairing plates 43 serve to make this heater pipe 11 andcondenser as a whole more efficient. The extraction piping is taken outthrough the center of the inlet 2 between fairing plates 43. The centerof the inlet is a region of low velocity steam flow, thus, such aplacement of these pipes prevents them from interfering with flow intothe dome. The fairing plates serve to cut down pressure losses whichwould result from the friction of steam flowing over the surface ofexposed pipes or from steam filling a space normally devoid of flow.

If desired, there may be included baflies 12, FIG. 4, for directing theflow of steam towards the tube bundle 5. These baflles are generallyknown and may be omitted, if desired, since their function is performedto a great extent by other parts of the steam dome of this invention.

The steam dome is primarily made up of an outer shell 14 of sheet orplate steel. Flow of steam from the turbine is in a downward direction.Plates 42 are mounted in the inlet to form a continuation of the guideand deflector plates in the turbine exhaust hood, and the steam flowsinto the dome through passages A around the periphery of the inlet. Thisleaves a center section through which the extraction piping may pass asexplained hereinbefore. The flow of steam into the steam dome produces avacuum which tends to collapse the outer shell. By this invention thereis provided an improved structure for supporting the outer shell andpreventing its collapse and which leaves the interior of the domeunobstructed thereby providing a better flow path.

This improved supporting structure includes a plurality of supportingribs 10. These ribs are mounted so that their longitudinal axes are in agenerally vertical direction and the width of each rib extends into thecavity of the dome. The thickness of each rib abuts the inside of theshell and is secured thereto by any suitable means such as welding. Theribs extend from a top closed ring or first structural member 20 towardsthe tube bundles 5, as clearly shown in FIGS. 1 and 4, and a bottom orsecond structural member 30. The ribs extend into the interior of theshell only a short distance, as is clearly shown in FIGS. 1 and 4.

The top structural member or ring includes a triangular structure alongtwo sides or ends of the dome adjacent the inlet and a channel orboxlike structure along the other two sides of the dome. The triangularportion of the ring 20 includes two side pieces 21 and 22 and the domeshell 14, as clearly shown in FIG. 2. There may also be a top piece 23to close the structure and provide a firm connection to the side wall ofthe inlet. The members forming the triangular structure are welded. Thistriangular section may be made of a single piece either in the form of atriangle with one side secured to the shell or an angle beam with theopen side secured to the shell so that the shell closes the triangle.

The channel member along the other two sides of the dome is best shownin FIGS. 4 and 5. This channel is made up of pieces 24, 25 and 26 andclosed by the shell 14; all welded together. If desired, the channel maybe a single channel with the open side welded to the shell or a box beamwith one side welded to the shell.

A lower structural member 30 extends only along the ends of the bottomend of the dome. This triangular member, as best shown in FIG. 3, ismade up of the outer shell 14 and two side pieces 31 and 32 which arewelded to from the structural member. Again, if desired, this may bemade from a one-piece structural member but with the construction shown,the size and shape may be varied more readily for different size andshape domes. For greater strength, the construction shown usesstructural members which, when in position and viewed in cross-section,form closed polygons. In some applications, however, it may be desirableto use structural members of other shapes.

Along the ends of the steam dome, the ribs 10 are connected between thetriangular portion of the upper structural member 20 and the lowerstructural member 30, as is clearly shown in FIG. 1. Along the side ofthe steam dome, the ribs are connected from the upper portion of thedome adjacent the channel 20 down to the supporting structure of thetube bundle 5. Where the ribs 10 abut the hollow beams 20 and 30, thesehollow beams may be solid as shown in FIG. 8. This may be done byextending the ribs 10 through the hollow beams or other suitable meansfor closing that portion of the beam.

The vacuum resulting from steam flowing into the dome causes a pressureto be exerted on the shell 14 when steam enters the dome through theinlet 2. This pressure loading is taken up by the ribs 10 which transferthe bending load to the top structure 20 and bottom structure 30 or tothe supporting structure of the tube bundles. The horizontal loadcomponent, formerly carried by the lattice work of the prior art, is nowcarried by axial and bending actions of the ring 20 and bottom member30. At the exit of the steam dome, the structural member 30 transfersthe vertical load component and part of the horizontal load component tothe foundation and substructure of the condenser through load transfermembers 35.

Additional support against a horizontal force may be provided by crossbracing such as shown in FIG. 6. This cross bracing or gridwork acts asa system of compression members and is similar to that used in prior artdevices in that it includes structural member 42 and cross braces 41.These cross braces are arranged so that extraction piping may be locatedin central section F, G, H, I. Cross braces 41, FIG. 7, may be at anangle other than 90 with respect to members 42 in order to conform tosimilar vane configurations in the turbine exhaust and eliminateinterference with steam flow. Although this cross bracing is best shownin the alternative embodiments of FIGS. 6 and 7, this bracing may alsobe used in the embodiments of FIGS. 1 -5.

If desired, the ribs which support the steam dome may be placed so thatthe steam is directed in greater amounts towards the cold end of thetubes and less amount towards the warm end of the tubes. Thisconfiguration is clearly shown in the modification of FIGS. 6 and 7. Itcan be seen that the ribs are placed farther apart at the inlet 2towards the cold end of the tube bundles than at the warm end of thetube bundles. This enables more steam to be directed towards the coldend creating a more effective steam dome and condenser. If desired, theribs 100 may be spaced equally at the inlet and unequally at the exittowards the tube bundle. The same results will occur by more steamflowing towards the cold end of the tube bundles than towards the Warmend. The structural members 20 and 30 of FIGS. 1-5 and 8 have beenomitted from FIGS. 6 and 7 for purposes of clarity but in actualconstruction are included.

In construction, the size of the dome and amount of steam flow areconsidered to determine the amount of pressure which will be exerted onthe shell. From this it can readily be determined how much load willhave to be absorbed by the structural members 20 and 30 and how farapart and what size ribs must be used.

It is essential that wherever there is a break in the structural members20 and 30 or the ribs 10, such as where the heater pipe 11 is located,some means such as the heater pipe itself must be included to transferthe load around this break. This is to guard against weak areas.

From the foregoing description it can be seen that a novel steam dome isprovided which has greater strength and allows an open area for easyflow of steam from the turbine towards the condenser. It is notnecessary to lace the heater pipes through the supporting structure asall the supporting structure is located adjacent the shell wall.Additionally, the flow is directed by the supporting ribs rather thanhindered by the supporting structure.

It is intended that the foregoing description be merely that of apreferred embodiment, and that the invention not be limited in any wayexcept by that which is within the scope of the appended claims.

We claim: 1. A dome for use in combination with a condenser comprising:

a shell having an inlet for receiving fluid to be condensed and anoutlet for discharging said fluid into a condenser;

first structural means mounted internally on said shell and circlingsaid inlet for supporting said shell and preventing said shell fromcollapsing inwardly around said inlet;

second structural means mounted internally on said shell adjacent saidoutlet for supporting said shell and preventing said shell fromcollapsing inwardly around said outlet; and

brace means mounted internally of said shell interconnecting said firstand second structural means for transferring a load on said shell tosaid first and second structural means and being dimensioned for guidingthe flow of fluid between said inlet and said outlet and located alongthe surface of said shell and adapted to leave the inside of said shellsubstantially unobstructed.

2. The dome of claim 1 wherein said first structural means includes aring extending completely around said inlet.

3. The dome of claim 2 wherein said ring includes side portions ofgenerally channel shape and end portions of generally triangular shape.

4. The dome of claim 1 wherein said first structural means is asubstantially hollow beam.

5. The dome of claim 1 wherein said second structural means includes agenerally triangular shaped member along the ends of the dome adjacentthe outlet.

6. -The dome of claim 1 wherein said brace means includes a plurality ofribs mounted so that their longitudinal axes extend along said shell ina generally vertical direction.

7. The dome of claim 6 wherein said first structural means is a closedring extending completely around said inlet and said second structuralmeans is a generally triangular shaped member along the ends of saiddome adjacent said outlet.

8. The dome of claim 6 further including cross bracing in the upperportion of the dome in said inlet.

9. The dome of claim 6 further including means to transfer the load onsaid dome to the lower substructure of said condenser.

10. The dome of claim 6 wherein said ribs are joined to the supportingstructure of the tube bundles of the condenser.

11. The dome of claim 10 wherein said ribs are spaced and located fordirecting a greater proportion of said fluid towards the cold end ofsaid tube bundles than towards the warm end.

References Cited UNITED STATES PATENTS 1,923,274 8/1933- Miller et al.165-159 2,111,240 3/1938 Grace 165-161 X 2,453,662 11/1948 Graham165-114 3,139,926 7/1964 Tinker 165-111 FOREIGN PATENTS 651,246 3/1951Great Britain.

r ROBERT A. OLEARY, Primary Examiner.

A. W. DAVIS, Assistant Examiner.

